A deoxygenation reaction of an epoxy compound to an alkene is a very important reaction in the fields of organic synthesis and biochemistry. With respect to the deoxygenation reaction of an epoxy compound to an alkene, the development of stoichiometric reaction using a variety of reagents has progressed (see, for example, NPL 1 and 2), but the catalytic reaction for deoxygenation has problems to be solved in that it is necessary to use a harmful reducing agent, that the reaction is likely to be affected by air or humidity, and that the catalytic activity is low (see, for example, NPL 3 and 4).
As a catalyst which enables the deoxygenation reaction of an epoxy compound to an alkene to be practically performed, for example, a silver-cerium oxide composite comprising a silver particle and cerium oxide covering the surface of the silver particle has been known. This silver-cerium oxide composite is produced by a method in which a silver solution and a cerium solution are individually changed to reversed micelle solutions, and the resultant reversed micelle solutions are mixed together to advance a redox reaction, and subsequently the micelles are caused to collapse using ethanol, and then the recovered material is calcined (see PTL 1).
However, in the above-mentioned reversed-micelle formation method, there is a problem in that the synthesis is conducted through a multi-stage process, and organic solvents and surfactants must be used, causing the time and cost to be increased. Further, there is a concern about the formation of fulminating silver which is an explosive substance. Fulminating silver is a mixture of silver nitride and silver amide, and could be generated when an aqueous ammonia solution of silver nitrate is prepared. As fulminating silver is very sensitive to an external stimulation, it is at risk of explosion caused even by slight friction, and a case in which fulminating silver actually exploded has been reported. The formation of fulminating silver can cause an accident and is a severe problem which must be avoided. Further, with respect to the reversed-micelle formation method, a method for produing a catalyst having a silver-cerium oxide composite supported on a metal oxide matrix material by a coprecipitation method has been disclosed. However, this method is likely to suffer reduction of the active surfaces due to the formation of macroparticles.